X = int(input())

if(X >= 30):
  print('Yes')
else:
  print('No') X = int(input()) X int(input()) int input() input if(X >= 30):
  print('Yes')
else:
  print('No') X >= 30 X 30 print('Yes') print 'Yes' print('No') print 'No' X = int(input()) int(input()) X
X = int(input())

if(X >= 30):
  print('Yes')
else:
  print('No')